1. Hitoshi Asaeda Nicolai Leymann
84th IETF, July 2012, Vancouver, Canada
IGMP/MLD-Based Explicit Membership Tracking Function for Multicast Routers draft-ietf-pim-explicit-tracking-01
Hitoshi Asaeda
Nicolai Leymann
84th IETF, July 2012

2. Objectives The explicit tracking function on routers works for:
Per-host accounting
Reducing the number of transmitted Query and Report messages
Shortening leave latencies
Maintaining multicast channel characteristics (or statistics)
84th IETF, July 2012

3. Open Issues in Interoperability with Non-supported Routers
In case when querier enables exp. tracking but non-querier does not support it
Querier does not query to confirm the last member (when it knows there are other members), but non-querier (who is a forwarder but does not know other members) may prune the state?
Querier
Forwarder S R1 R2
84th IETF, July 2012

4. Open Issues in Interoperability with Non-supported Routers
Possible solutions
Disable exp. tracking function when adjacent router(s) exists or “I am not the forwarder”?
Existence of adjacent router is known when [Other Querier Present Interval] is not 0?
But routers SHOULD be able to configure disabling this disable function to avoid DoS
Define new IGMP/MLD message for informing that querier/non-querier(s) enables/disables exp. tracking and synchronizing the behavior?
Work well for the standard IGMP/MLD without doing anything?
Other Querier Present Timeout = Rob_Var (2) x Query Int. (125 sec.) x Query Response Int. (10) x 1/2 = 1250 sec.
Tuning Other Querier Present Timeout shorter (e.g., 10 sec.) ?
84th IETF, July 2012

5. Next Step Intended status Address open issue WGLC after revision ?
Informational RFC ?
Address open issue
Interoperability
WGLC after revision ?
84th IETF, July 2012